1. Field of the Invention
The present invention relates to an apparatus for opening and closing covering means for a furniture raising/lowering type floor equipment employable for a building such as a hall, a theater, a gymnasium or the like. More particularly, the present invention relates to an improvement of the apparatus for opening and closing covering means for a furniture raising/lowering type floor equipment wherein the covering means in the form of a rigid cover plate, a flexible cover plate or the like can smoothly be opened and closed so as to allow furnitures such as chairs, tables or the like to be raised up above the floor surface of a building such as a hall, a theater, a gymnasium or the like to assume an operative attitude and lowered below the floor surface of the same to assume an inoperative attitude.
2. Description of the Related Art
In recent years, a building such as a hall, a theater, a gymnasium or the like has been increasingly utilized in a multi-purposed fashion. To this end, research and development works have been conducted for providing various kinds of furniture floor equipments. As is well known, this kind of furniture floor equipments are generally classified into two types, i.e., an expansible/contractible platform displacing type floor equipment and a furniture raising/lowering type floor equipment. An item of the present invention belongs to the latter type of floor equipment, i.e, a furniture raising/lowering type floor equipment.
For the purpose of simplification, description will be made below with respect to a most popular chair raising/lowering type floor equipment. The conventional chair raising/lowering type floor equipment is usually constructed such that a plurality of chairs (an array of chairs jointed to each other in the side-by-side relationship as seen in the transverse direction) are mounted on a raising/lowering unit for a building such as a hall, a theater, a gymnasium or the like so as to enable each audience to enjoy a performance while sitting on a chair allocated to him. When the chairs are to be in use, an operator turnably opens a cover in the form of a flat plate for the chair floor equipment by driving a driving unit so that the chairs are raised up above the floor surface of the building through the opening portion of a chair accommodating chamber to stand upright thereon and they are then slightly inclined in the rearward direction. At this time, the cover is held in the upright standing state behind an array of chairs. At this time, the cover is merely an obstacle. Thus, an appearance of the chair floor equipment is degraded unavoidably. This is not acceptable also for the building from the viewpoint of an aesthetical property of the building.
When the performance is over, the chairs are lowered in the chair accommodating chamber below the floor surface of the building while they are flatly folded. Subsequently, the operator turnably closes the cover to shut the opening portion of the chair accommodating chamber with the cover so that the cover is flush with the floor surface of the building and becomes a part of the floor surface of the same without any unnecessary projection thereabove.
Since the cover for the chair raising/lowering type floor equipment is constructed in the above-described manner, when the chairs are to be in use, the cover which has been laid over the opening portion of the chair accommodating chamber below the floor surface of the building is turnably opened to stand upright behind an array of chairs as a kind of visually unacceptable obstacle. This leads to the result that a considerably large space is unavoidably occupied by the cover on the floor surface of the building, resulting in an aesthetic property of the chair raising/lowering type floor equipment as well as the building being degraded undesirably.